Ovens that apply water for cooking are well known in the market of domestic cooking ovens where there is the need for steam cooking or the need for using water as an ingredient in certain recipes such as the preparation of pasta or the dough of a pizza. Some microwave ovens are provided with a bowl and a stirrer in which the user will add the solid contents of a food package (with well defined amount of ingredients) wherein a pump in the oven feeds a predetermined amount of water in order to obtain a final food preparation after the cooking or heating procedure. In these types of cooking processes a very precise amount of water must be added to the container or bowl, but it is also necessary to avoid water that may remain in the piping assembly, particularly in the piping downstream from the pump. The need to remove water downstream from the pump derives from the possibility that water in the piping assembly can be heated by either microwaves or by convection from the heated cavity. In addition, certain recipes need to avoid unwanted dripping of water during the cooking process or the generation of steam. Moreover, water remaining in the piping system can also lead to deleterious results in terms of food safety standards.
In order to solve the above problems, i.e. accuracy in water dosing and drainage of piping system, known solutions comprise the use of positive displacement pumps with a bi-directional operation in which the flow of water can be easily reversed by changing the rotation direction of the motor. Such pumps are for instance peristaltic pumps, gear pumps or flexible impeller pumps. These known solutions have the drawback of an average high cost. For instance, peristaltic pumps are mainly used in laboratory equipment and their average cost is too high for application in small domestic appliances such as microwave ovens or the like.
It is therefore an object of the present disclosure to provide a domestic oven that can add an appropriate amount of water for cooking while eliminating residual water in the piping assembly.